The graph was built using data from the Echo Nest API and laid out using Gephi. According to Lamere the network was built using the following:

I collected the top 2,000 or so terms via the Echo Nest API. For each term I calculated the most similar terms based upon artist overlap (for instance, the term ‘metal’ and ‘heavy metal’ are often applied to the same artists and so can be considered similar, where as ‘metal’ and ‘new age’ are rarely applied to the same artist and are, therefore, not similar)

For those interested, appart from the Echo Nest API, other music online services offers APIs. Here you have the links

This is ultra-cool. I have been working on cataloguing music my self for many years and am pleased to know I was thinking along similar lines but did not have the technology to expand to cover all of the music “echo-audio-sphere”.

I would love this map to be more interactive so I can click on a entry and be zoomed in to the 1st degree of separation. Any thoughts of trying to use google mapping technology on this or one of the open map API’s to make it faster and more interactive? It appeals to me as geographic map and I want to treat it that way so I can explore the categories dynamically.